Ultrasound-guided Lavage of Calcific Deposits of the Rotator Cuff

Inclusion Criteria: * Patient aged 18 years and older * Pain in the deltoid region worsening with activities above shoulder level and/or at night with a calcific deposit * Ultrasound evaluation of the calcific deposit with type I or II characteristics, a solitary conformation, a minimum size of 1.0 x 0.5 x 0.4cm (length x width x depth) and without clear signs of resorption (PDUS grade 0 - I°, see study procedure). * In case of multiple calcific deposits, it has to be warranted that the other deposits are smaller than the minimum size of 1.0 x 0.5 x 0.4cm and with no signs of PDUS signals. * Qualification for more intensive treatment on account of no clinical improvement after a minimum of 3 months with conservative treatment (physical therapy and oral anti-inflammatory drugs). * able to understand the content of the patient information / consent form in German and give consent to take part in the project Exclusion Criteria: * Previous UGPL or surgery of the affected shoulder * Treatment with subacromial injection (SAI) or ESWT in the three months before inclusion * Other causes of shoulder complaints (e.g. rotator cuff tear, frozen shoulder, inflammatory arthritis, bursitis, …) * Intervention failure (no retrieval of calcific material, leakage of the injected saline, disruption of the calcific rim or distribution of calcific material) * Patients with a language barrier hindering questionnaire completion * Pregnancy